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Full text of "Economics of cement dispersion."

/3of-^ 



RESEARCH PAPER NUMBER THIRTY-SEVEN 



RELATION OF DISPERSION 

TO 

SPECIAL CEMENTS „ '. ' 

'*tt21942 



I 



BY 

EDW. VV. SCRIPTURE, JR., PH. D. 

DIRECTOR 

Master Builders Research Laboratories 
CLEVELAND, OTU« \ 



COPtfSJGHT l^V"' THE ;M;A€Ur GUILDERS COMPANY 



FOREWORD 



APPLICATION of the principle of dispersion to 
Portland cement has received widespread recogni- 
i ion by the construction industry in large defense 
construction as well as other building. In previous 
ers this principle has been described in its relation 
in normal portland cement and the economy of its 
application to concrete mixes has been shown. 

1 ! always several means of accomplishing 

ed result and it is no more than reasonable to 
select that which is most effective and economical. In 
concrete to-day, the special cements offer means of 
securing certain specific properties desirable for 
ticular structures and it seems appropriate to consider 
their relation to cement dispersion. This paper has 
been prepared to give the construction industry in- 
formation on this subject. 

Cement dispersion will accomplish many of the 
objectives sought in the use of special cements. More- 
over, it is not incompatible with them but, on the 
contrary, is equally effective with the special cements 
as with normal portland cement in improving the 
properties of concrete. As a result it is found that^in 
many cases, the desired properties can be secured with 
a normal portland cement and a dispersing agent more 
economically than with a special cement and without 
jome of the disadvantages which the latter may have. 
In other cases it is shown that the desired end can he 
realized most effectively and economically by app 
tion of the principle of dispersion to the special cement. 

Believing that knowledge of these relations will be 
of value to the construction industry whenever the use 
of a special cement is contemplated for some specific 
purpose, The Master Builders Company has published 
this paper. 



ABSTRACT 

This paper reviews briefly the mechanism whereby greater efficiency 
lined through dispersion. The effect of this action on 
the | es of concrete and the relation of cement dispersion to 

economy are reviewed. 

The various usual types of special cements and the particular 
• tiance are described. These include: 

High 1 Type III for high early 

' 'IS. 

Type V for resistance to 

sulphate CO! 

1 1 and [V for reduction of heat 
• lution. 

eat e\ olution and corro- 

•• increased workability and 
dui 

' Ified workability and 
luction in capillary attraction. 

dispersion is applicable to these 

at ii is to normal Portland cement 

• ame effect on the special 

ed for a given consistency and in 

or hydratioi i titly 

Liability, watertight i time 

i rsion and sp- 
me relation to tl 
e properties of tl 

rable prop. 



RELATION OF DISPERSION TO SPECIAL CEMENTS 



Table of Contents 

Page 



Introduction 



Mechanism of cement dispersion 6 

Effect of dispersion on properties of concrete 7 

Economics of cement dispersion 7 

Types of Cement 

High Early Strength cements 10 

( lorrosion Resistant cements .14 

Low Heat cements .17 

Pozzolan cements 20 

Natural cement blends 22 

( Vments with grinding aids 26 

Waterproof cements 30 

Summary 32 



w 



RELATION OF DISPERSION TO SPECIAL CEMENTS 
INTRODUCTION 

THE mechanism whereby dispersion of portland cement profoundly 
affects the properties of concrete has been described in a previous 
paper (Research Paper No. 35). In another paper (Research 
Paper No. 36) the economic aspects of this principle have been dis- 
cussed, specifically in comparison with addition of extra cement to the 
mix. This material is briefly reviewed in the following three sections. 

Nature of Cement Dispersion 

Application of the principle of dispersion to hydraulic cements has 
recently assumed considerable importance in concrete construction and 
has found widespread use in the present defense building program. 
Dispersion of finely divided solid material in a liquid is not in itself 
new as it has been employed in ceramics, dyeing, and other fields. 
Dispersing agents are, however, specific in nature so that a reagent 
which acts to disperse some particular solid-liquid system may or may 
not act in a similar manner in some other system. Furthermore, an 
effective dispersing agent may interfere with other reactions of the 
system. The use of dispersion in the field of concrete and mortar has 
awaited the development of effective cement dispersing agents which 
would not interfere with the normal reactions of hydraulic cements. 
Such reagents were discovered about 10 years ago and since that time 
have been developed in the laboratory and in the field so that they are 
now established as a practicable means of considerable importance of 
improving the properties of concrete. 

When portland cement is mixed with water the individual particles 
tend to gather together and stick to each other in clumps, i.e.. the 
sohd-hquid system is flocculated. This is due to lack of mutually 

Fig. I 




Cement Suspended in Water Cement Suspended in W T ater 



Undispersed 



Dispersed 



[6] 



repellent electrostatic charges on the cement particles. If a suitable 
dispersing agent is introduced into the mix the clumps are broken up 
and the cement then acts as individual particles, i.e., is dispersed. 
cf. Fig. I.) 

Dispersion of the cement produces two important effects. The 
water which had been trapped within the particle clumps is released to 
become a part of the mixing or placing water. The surface area of the 
cement in contact with water is greatly increased since the particles 
are no longer in contact with each other. As a result of the first the 
amount of water required in the mix for a given consistency is less, i.e., 
the water-cement ratio is reduced. Since the value of the cement is 
dependent on a hydration reaction which is a surface phenomenon, the 
second effect which promotes more rapid and more complete hydration 
permits more efficient utilization of the cement. By the reduction in 
water-cement ratio and by the increase in surface area of cement 
available for hydration the potential value of the cement is more 
completely realized. 

Effect of Cement Dispersion on the Properties of Concrete 

Those properties of concrete which are dependent on the surface 
area of the cement and on water-cement ratio, and this includes most 
of them, must necessarily be improved by dispersion. These effects are 
realized in the concrete in both its plastic stage and subsequent to 

hardening. 

During the plastic stage dispersion of the cement in a given mix 
will produce more placeable concrete with less water due to release of 
water from the cement clumps. The fattiness of the mix is increased, 
while segregation and bleeding are reduced, due largely to the increased 
effective surface area of the cement. Volume change before hardening 
is markedly decreased due in part to the lower water content and in 
part to the greater surface area. 

A greater uniformity and freedom from gross defects of the hardened 
concrete may be expected from the improved properties in the plastic 
stage. Greater watertightness with reduced permeability and absorp- 
tion are realized through the lower water content required for placing. 
Higher strengths and very greatly increased durability with respect to 
both freezing and thawing and sulphate corrosion may be attributed to 
the lower water-cement ratio of the dispersed mix and to the increased 
surface area available for hydration. 

It is not suggested that cement dispersion is a panacea for all ills. 
Poor concrete will continue to exist due to poor workmanship, poor 
mix design, defective materials or other causes whether the cement 
used is or is not dispersed. What cement dispersion will do is improve 
the quality of good concrete or minimize the defects of poor concrete 
by attacking the problem along the fundamental line of using the 
cement more effectively. 

Economics of Cement Dispersion 

Granted that the application of the principle of dispersion to cement 
will produce definitely large improvements in the properties of the 
concrete the question will naturally arise whether the value of the 

[7] 



r 



improvement is greater than the cost of dispersion. The economies to 
be effected will lie in the original cost of the materials making up the 
concrete mix, in the initial cost of the concrete in place as affected by 
workability, segregation, etc., and in the eventual cost of the structure 
as determined by maintenance and length of life of the structure. 

The last two of these are somewhat intangible and difficult to 
express in specific monetary terms. There can be little question that a 
more placeable concrete with less tendency to segregation will reduce 
labor costs in placing, finishing, patching, and rubbing. \\ hether these 
savings in themselves will pay for the cost of dispersion will depend on 
the conditions on any particular job. Likewise it is hardly to be doubted 
that a more watertight durable concrete will reduce the cost of main- 
tenance and effect a saving by extending the life of the structure. 
Whether the savings so effected justify the cost of dispersion will depend 
on the severity of the conditions to which the structure is exposed. 

Material costs can be compared much more definitely and are of 
general applicability. A suitable basis of comparison can be found in 
the relation between cement dispersion and the amount of additional 
cement required to produce similar results. Although there will be 
minor variations in different localities the cost of dispersion in an 
average concrete mix of between five and six sacks of cement per cubic- 
yard may be taken approximately to equal the cost of adding three- 
quarters of a sack of extra cement. 

Data have been accumulated both in the laboratory and in the 
field which show that dispersion of the cement in a given mix will pro- 
duce a strength equal to or greater than one additional sack of cement, 
will produce greater workability with respect to both mobility and 
cohesiveness, greater durability with respect to resistance to both 
freezing and thawing and sulphate corrosion, and will increase water- 
tightness with respect to both absorption and permeability to a greater 
extent than will one additional sack of cement. Further, dispersion of 
the cement will reduce volume change and will decrease heat evolution; 
entirely beneficial results whereas additional cement will have the 
opposite effects. 

In view of these results it is evident that cement dispersion is a 
more economical means of producing a desired effect than is the addi- 
tion of extra cement. How this economic advantage will be utilized 
will depend on the requirements in each case. When high quality is not 
a factor it will be used to produce a given quality of concrete at a 
lower cost. Where quality is the primary consideration dispersion will 
produce maximum quality at a given cost. 

It is generally recognized that there are many other methods of 
modifying one or more properties of concrete than that of additional 
cement and it would seem appropriate to consider the relation of dis- 
persion to these. 

The properties of concrete are influenced both by the nature of the 
materials from which it is made and the proportions in which they are 
assembled or the mix design. It is not proposed to deal with the purely 
physical aspects of mix proportions or characteristics of the aggregates. 

[8] 



It is assumed that advantage will have been taken of these factors 
within the limitations of available materials. It is proposed to consider 
here the benefits and disadvantages which are derived from some 
modification of the cement itself, that is, the use of special cements. 

TYPES OF CEMENT 

Portland cement is composed of a number of compounds, chiefly 
of lime, produced by burning together calcareous and silicious materials 
and grinding the resultant clinker to a certain degree of fineness. The 
more important chemical compounds of portland cement are, tricalcium 
silicate (CaS), dicalcium silicate (C2S) and tricalcium aluminate (C.3A). 
These constitute the bulk of the cement and more is known concerning 
their influence on the properties of the cement than is known con- 
cerning a considerable number of other compounds present in relatively 
small amounts. 

It has been realized for a long time that the properties of portland 
cement could be materially altered by modifications in its process of 
manufacture. This has been given recognition by the recent adoption 
by the A.S.T.M. of five official classifications of portland cement. The 
principle factors influencing the properties of the cement are: 

1. Its compound composition which in turn is influenced by the 
nature of the raw materials and the burning process. 

2. The fineness to which the cement is ground, i.e., its surface area. 

3. Additions of more or less reactive materials to the cement, 
usually during grinding. 

The rate of cooling of cement clinker has an influence on the prop- 
erties of the cement but this may be included as part of the burning 
process. 

The five types of cement recognized by A.S.T.M. standards are 
as follows: 

Type I. Normal portland cement 

Type II. Moderate heat of hydration cement 

Type III. High Early strength cement 

Type IV. Low heat of hydration cement 

Type V. Corrosion resistant cement 

Cements falling under any of these types may be further modified 
by additions of less than V f of extraneous materials, usually grinding 
aids, under certain conditions. There are also various other types of 
cements such as blended cements, masonry cements, natural cements, 
etc. Additions of extraneous materials other than those recognized by 
the A.S.T.M. have also been used. The various modified cements 
discussed in this paper are as follows: 

1. High early strength cements 

2. Corrosion resistant cements 

3. Moderate or low heat of hydration cements 

4. Pozzolan (blended) cements 

5. Natural cements 

6. Cements with grinding aids 

7. Waterproof cements 

[9] 



ould be pointed out that the reason for the development of the 
special or modified cements has been the feeling that while normal 
Portland cement has proved and still is eminently satisfactory for most 
purposes, in certain applications one or more properties in a higher 
degree than they would be present in normal portland cement would be 
advantageous. This has meant, usually, that in the special cement, 
one property has been markedly enhanced without much change in or 
at the expense of the otb 



I. High Early Strength Cement 

As its name implies, an high early strength cement is one in which 

lgth develops rapidly. This effect mav be produced in three ways 

1 by altering the compound composition, increasing CaS and possibly 

I A. at the expense o- - 2 finer grinding to produce Greater surface 

area, and 3 the addition of an accelerator. 

The advantages of high early strength are well known and need no 
more than passing mention. They include more rapid rate of con- 
struction more frequent reuse of forms, reduced curing costs, and 
earlier utilization of the structure. 

The disadvantages of high early strength cements are that usually 
a higher water-cement ratio is required for a given consistency and a 
more rapid rate of heat evolution produces greater temperature rises in 
concrete. The setting characteristics of the cement mav also be altered 
so that they may affect finishing operations adversely. This la*t 
however, does not appear to be necessarily the case 






TABLE No. I 

High Early Strength cement and Normal Portland cement with 
Dispersing Agent Mod. 



Concrete Mix -Cement 
: nd 

Slump 



447 lbs. 
1346 lbs. 
lbs. 
3 1 1 inches 



High Early Strength Normal Portland Cement 



Gallons water per cu. yd. 
Compressive Strength* 
Lbs. per sq. in. 
ldav 

2 dk 

3 da 

7 days 
10 davs 
28 lavs 



Cement 



860 
177«» 
221o 
3120 
3180 
3760 



Average for three separate series. 



with Dispersing Agent mod. I 
31 



1010 

173o 

3210 
3390 



[10] 






\\ hether a high early strength cement should be used in any 
specific case depends on the relative importance of speed and the other 
properties of the concrete. The properties of concrete made from high 
early strength cement, aside from the early development of strength 
are probably not affected to any marked extent, except in the case of 
large masses where temperature effects are of prime importance. On 
the other hand they are not improved in comparison with a similar 
concrete made from normal port land cement and properly cured. There 
is some reason to believe that the slower development of strength of the 
normal Portland cement has some beneficial effect on the ultimate 
properties of concrete. Where speed is a primary requisite or is of pre- 
dominant importance then the use of a high early strength cement 
should be considered as one means of realizing this objective. It will be 
considered, presumably, on the basis of economy, that is, whether it is 
the least costly way of securing the desired strength at early ages. 

Two other methods of producing high early strengths immediately 
suggest themselves. These are the use of additional cement (normal 
Portland) and dispersion. With respect to the former, sufficient addi- 
tional cement will undoubtedly give strengths equal to those of high 
early strength cement. The use of additional cement to accomplish this 
purpose involves the disadvantages of higher volume change and heat 
evolution. Furthermore it seems hardly possible that equal strengths 
can be secured by the addition of an amount of portland cement equal 
in monetary value to the increased cost of the high early strength 
cement. Were this the case, high early strength cements would have 
no economic justification. 

Fig. II 



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SAND 1346 LBS. 


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STONE-*. 1988 LBS. 




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SLUMP_ 34 IN. 








WATER 
































Normal portland- Dispersed 31 gals. "" 








II 



















Age in Days 
[ll] 



Dispersion of the cement will increase the strengths at all ages, 
necessarily including the early ages. This is due first to the reduction 
in water-cement ratio made possible by dispersion and second to the 
higher surface area made available for hydration. With a slight 
modification the use of a cement dispersing agent in the mix will give 
with normal portland cement early strengths equal to those of high 
early strength cement and higher strength at later ages (Table I and 
Fig. ID. Likewise the dispersing agent will produce strengths at early 
ages higher than one additional sack of cement (Fig. III). 

Fig. Ill 



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Age in Days 

It should be noted that, although these relations between high early 
strengths and normal portland cements hold in a general way, there are 
considerable variations between different brands of cement. Thus, with 
an high early strength cement which gives unusually high early strengths 
and a normal portland which gives lower than average early strengths, 
the latter used with the dispersing agent may fall somewhat below the 
former. Conversely, with an high early strength cement of lower than 
average and a normal portland with higher than average early strength, 
the latter when dispersed may give considerably higher strengths than 
the former. This is to say that the relative early strengths for the 
high early strength cement and the dispersed portland cement in any 
particular case will depend on the relation between the particular 
brand of each which is being used, but in general, with average cements, 
the early strengths will be approximately the same. 









[12 



The economic relations of these three methods of securing early 
strength can now be considered. Dispersion will cost approximately 
$0.40 per cu. yd. for an average concrete mix. One additional sack of 
cement will cost approximately $0.50 per cu. yd., and the use of a 
high early strength cement instead of normal portland cement about 
$0.70 per cu. yd. It is evident that the most economical way to secure 
the desired early strength is by cement dispersion. 

There are certain advantages, in comparison with the use of high 
early strength cement, in securing the required strength by cement 
dispersion. Since, by this means, the increases in early strengths are 
secured in very large part by reduction in water-cement ratio the heat 
evolution will be much less. The setting characteristics of the concrete 
are not appreciably altered. Since dispersion permits a large reduction 
in water-cement ratio the well-known advantage of lower water-cement 
ratio such as increased durability, increased watertightness, and 
decreased volume change are also realized. 

It should not be overlooked, however, that there is no incompati- 
bility between a suitable cement dispersing agent and an high early 
strength cement. Actually, since the finer high early strength cements 
show an even greater tendency toward flocculation than the coarser 
normal cements, cement dispersion is even more effective. Therefore, 
dispersion of the high early strength cement will produce still higher 
early (and ultimate) strengths as well as the other advantages of lower 
water-cement ratio. Strength curves for an high early strength cement, 
dispersed and undispersed are given in Fig. IV. 

Fig. IV 





























































































































































































































































































































































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CONCRETE MIX 

CEMENT . 447 LBS. 
SAND 1346 LBS. 
STONE- 1 1988 LBS. 
SLUMP 2| IN. 
WATER 

Undispersed Cement. 38 gals. 
Dispersed Cement „ 33gals. 




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Age in Days 
[13] 



In this connection a comparison may be made, from an economic 
point of view, between dispersion and approximately one additional 
sack of high early strength cement. These will both give about the 
same strength Fig. A' . Cement dispersion, for an average concrete 
mix. costs about $0.40 per cu. yd. while the additional sack of high 
early strength cement will cost about $0.63. The conclusion is inevit- 
able" that the more economical way to secure high early strength is by 
cement dispersion. 

Fig. V 






i.:: 



K 






X 

*7 




CONCRETE MIXES 

HIGH EARLY STRENGTH CEMENT 

DISPERSED UNDlSPERSED 

iz: - ;s*. sacks 

337 LBS. ....CEMENT 44.7 LBS. 

i 390 LBS SAND 1346 LBS. 

2056 LBS STONE-f. ...1988 LBS. 

33 GALS WATER 39 CAiS. 

3 IN SLUMP. 2i IN. 



• i 2 3 4 s e - fi 9 io :; : = 

Age in Da 

Three methods of securing higher early strengths have been con- 

of high early strength cement, use of additional normal 

and cement, and the dispersion of the cement normal portland . 

— . the most economical is dispersion and this has the added 

. : improved properties springing from a lower water-cement 

ratio. When exceptionally high early strengths are required the most 

omical method of realizing them is by the use of a cement di 

with an high early strength cement. 

II. Corrosion Resistant Cements 
Corrosion resistant cements are designed to resist the efTec 
corrosion, particularly by sulphate solutions including sea water. This 
is accomplished primarily by the reduction of the ntent of the 

cement as this is the compound most readily attacked by sulpha 
A comparison of a normal portland cement Type 1 with a coma 
resistant cement Type V is shown in Fig. VL 

Reduction of the CiA content of the cement reduces the rate and 
amount of heat evolution which would appear to be a desirable effect. 






It also tends to retard setting and rate of hardening which is not un- 
desirable except where speed of construction is a factor. Apparently the 
other properties of the concrete are not materially affected. 

Where resistance to corrosion is important, as in structures exposed 
to sea water, to sulphate bearing ground waters, and to highly polluted 
atmospheres there would appear to be good reason for the use of 
corrosion resistant cements. There is no economic reason why, under 
such circumstances, corrosion resistant cements should not be used 
as these are usually obtainable at no increase in cost over normal 
Portland cement. 

Fig. VI 




A. Normal portland cement 

Compressive strength at 28 days — 4660 lbs./sq. in. 
After 2 years in 8% Magnesium Sulphate (changed weekly) 





B. Corrosion Resistant cement 

Compressive strength at 28 days — 5200 lbs. sq. in. 
After 2 U years in 8% Magnesium Sulphate (changed weekly) 



[15] 



Dispersion will increase resistance to corrosion because of reduced 
permeability of the concrete, increased hydration under Riven curing 
conditions/and improved structure. Additional cement will also in- 
crease resistance to corrosion due to increased strength and lower 
permeabilitv. The decrease in sulphate corrosion secured by dispersion 
-•ater than that secured by addition of one extra sack of cement 
Since the cost of dispersion is less than one additional sack 
of cement the more economical \\; cure corrosion resistance with 

normal portland cement is to design the mix with a dispersing agent. 
Moreover the other advantages of dispersion compared with additional 
cement with respect to strength, resistance to freezing and thawing, 
watertightness, volume change, workability and heat evolution are also 

Research Paper No. 36 . 

Fig. VII 
Magnesium Sulphate kly) 




Vdditiona 




<- 1 
use of a the 









relative degrees of corrosion resistance of the two particular cements 
selected as there are considerable variations within each type. 

Where corrosion resistance especially is sought it would seem desir- 
able to use a corrosion resistant cement of Type V if available. Cement 
dispersion, however, is equally applicable to a Type V cement as it is 
to a Type I cement because both are naturally flocculated. The same 
advantages with respect to workability, strength, durability and other 
properties, including resistance to corrosion are secured. Data on the 
effect of a dispersing agent on a corrosion resistant cement are given 
in Table II. 







TABLE 


No. II 

Undispersed 


Dispersed 


Cement 






585 


585 


Sand 






1171 


1171 


Stone — %" 






2049 


2049 


Water 






38 


33 


Slump 






1H 


\y 2 


Compressive 


Strength - 






Lbs. per sq 


. in. 


- 28 days 


5200 


6370 



Here it will be seen that dispersion has similar effects with this type 
of cement to those which it has with a normal Portland cement. Con- 
sequently, for a given degree of corrosion resistance it will be most 
economical to design the mix with a Type V cement and a cement 
dispersing agent or for a given cost the highest resistance to corrosion 
can be secured in this manner. 

III. Low and Moderate Heat of Hydration Cements 

Cements with low heats of hydration were developed to circumvent 
the deleterious effects of rapid rate and total amount of heat evolution 
in raising the temperature of the concrete, particularly in mass con- 
crete. There is some reason to believe that these heat effects are also 
of more importance in thinner sections than has usually been believed 1 . 
The reductions in heat evolution are secured by reduction of the C:jA 
content, or increase in the C2S content at the expense of the CaS, or both. 

These cements have somewhat slower rates of setting and hardening 
than normal port land cement. Except when speed of construction is a 
factor this is probably beneficial rather than detrimental. Resistance 
to sulphate corrosion is usually improved. It does not appear that the 
other properties of the concrete are materially affected. 

The difference between the low (Type IV) and the moderate 
(Type II) heat of hardening cements is one of degree rather than of 
kind. The low heat cement is not generally available, being supplied 
only in special cases for large mass concrete projects. The moderate 
heat of hardening cement is available in many markets and is frequently 
the same as or interchangeable with the corrosion resistant cements 
(Type V). These cements are usually supplied at no increase in cost 
over that of normal portland cement so that there is no economic 
reason why they should not be used where heat evolution is an im- 
portant factor. 

*L. A. Forbrich — J. A. C. I., Sept. 1941. 

[17] 































































































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I 




THE EFFECT OF 
DISPERSION ON THE 

EARLY HEAT 

LIBERATION OF 

A NORMAL 

PORTLAND CEMENT 

(TYPED 








I 1 




1 






If 






















c 


* 




1 

* §7 






/. 








( 


















* 






























r -/ 
























J" 


























/ / \ 












































- 


F A l\ 






































1 
















A \V 
























; / 








1 












tff 
















fnOyRSAF 


FIXING 





Fig. VIII 













THE EFFECT OF DISPERSION ON 
THE EARLY RATE OF HEAT 
LIBERATION OF A MODIFIED 
LOW HEAT CEMENT (TYPE H) 


B 






























































































































































































2 












































3 






































































































ft 
























1 






rfy 


















£Y 






















// t 


?, ^ 




















/ 














s 


/ 47 


X. ^S-^ 




f Jtf >^:^> 


















■^V^ _^^ |HOURS AFTER MIXING] 






1 






















N 






i 






?o 




M 



TABU] No. HI 

Ileal of Solution 



■ I 
: I I 
. I 
• I I 

Type III 

5 





Ileal Hydration 


( londil ion 


Ca 
3 days 


. per gram 
7 days 28 d; 


I Fndispersed 


70 


85 1 


10! 


I dispersed 


71 3 


88 


99 2 


I Ihdispereed 


64 8 


80.7 


91.8 


rsed 


64 


80.7 


90 9 


I rndispensed 
1 dispersed 


65 3 
67 9 


77.2 
77.2 


92.2 
92.8 


l Ihdispersed 


77 5 




97.1 


rsed 


7!* 7 


90 1 


99 


1 'no 


7 


• 


76 


I tadispei 
rsed 


71 7 

t:> i 


B4 4 

B4 9 






6 7 


69 2 






2 










lar effecti wii li 

if I) normal Portland i i 

ater-tighl 






A further advantage of cement dispersion is found in the effect on 
heat evolution. Dispersion of a low or moderate heat cement in a given 
mix does not appreciably affect the rate or amount of heat evolution 
(Table III and Fig. VIII). Within the limits of accuracy of the deter- 
minations there are no differences in heat evolution for the dispersed 
and undispersed conditions of each cement. Therefore, a mix with a 
lower cement content and a lower rise in the temperature of the concrete 
(Fig. IX) can be designed using a cement dispersing agent at a lower 
cost, with equal or greater strength, and with equality or superiority 
with respect to other properties. 



Fig. IX 



5 — 

LLt 


— i— i 1 1 1 !— * 

MOD F ED 10 


Li/ 




/IT 




en 






r/ 








. 








W nc 


Al K. 


cm en 


u rrcu; 










































"8T 


































S_ 


































™ ft + 


































70 ■- uj 


































o 


































1 


































- UJ 
60 w + 


































DO ■ r 52 






















*rr*/r iVi> /W K/7 , 


cZ 








tcj^BAR^^^riZL 




£ 


O *seo& 








3 


Wz&r 


^&rZZ.,nBA&W 


„ Or tOT*"' 


50-" Si 




s&f 


WW T 1 














1- 


f£*rf&2 


^^^BWeLOFCWtfi 


//■ 




.A 5 -JU 


--j**?tS* 


& 


pi 


QftXrlV-* 






















4° £ if 
































^ 11 A 


































1«a:h7~~7 




































































iff 






























J - 






Tijr rr 


FECT OF DISPERSION ON 
IMPUTED ADIABATIC, 
"EMPERATURE CURVES FOR 
^L MASS CONCRETE MADE 
MODIFIED LOW HEAT CEMENT 




THE LI- 


on III 


THE C 


iflf 


TIME-1 




TYPICA 




IA/ITU J 


|0 


Wl I H > 




































o I I I I 

n i 1 


1 AGE IN DAYS h 

■t 


















28 



The situation also may arise where low heat evolution is desired but 
rather higher strengths at the early ages are required than would be 
secured with the low heat cements (Types II and IV). In this case it is 
possible to take advantage of the fact that dispersion, with normal 
Portland cement, will permit use of a minimum cement content for the 
required strength. Since the heat evolution is not materially affected 



[19 1 



by dispersion this means that the temperature rise in the concrete for a 
given strength at the earlier ages is reduced as is illustrated in Fig. X. 

Fig. X 









n^ r-i i i ■ ■ ' i ! : 

^NORMAL PORTLAND CEMENT (TYPE I) f 


















































3 






























































































i 












































70 . 


> 


























scoter* rt)NCR£TE 






c 


a 












^J&ffirJSLcuw- . 








i 








</"^^^-— 






















f.v 




































1 


































































































/-/ia//-#£T£ 


















(■*■■ 


risers***?. ^Zmcnt />£* 






L 


; f 




„fl K " 




















< 


\ / J^ 


^ _l 
































"""if 


: / 










































[f t 














































J J 


































































































THE EFFECT OF DISPERSION 
ON THE COMPUTED ADIABATIC, 
TIME-TEMPERATURE CURVES FOR 
TYPICAL MASS CONCRETE MADE 
WITH NORMAL PORTLAND CEMENT 






30 ■ i 






























" 1/ 
















































10. 






















































































































































1 






















— 












1 








i 


^r- 


kT . 


^ 





















13 7 28 

Where the heat evolution of the concrete is a primary consideration 
a low or moderate heat of hardening cement should be selected. A mix 
should then be designed, using a suitable dispersing agent, with mini- 
mum cement factor consistent with the required strength and quality 
of concrete w.'th respect to other qualities. 

IV. Pozzolan Cements 

A pozzolana is a material, usually of a silicious nature, which 
will combine with lime in the presence of water at normal temperatures 

form cementitious compounds. It may be of natural or synthetic 
origin. When added to a Portland cement mix a pozzolanic material 
will combine, more or less rapidly and completely, with the free lime 
the cement. This reaction produces desirable results, particularly 
with respect to corrosion resistance, on the properties of the concrete 
but i he extent of the improvement effected varies widely with the 
nature of the pozzolanic material. 

From time to time special pozzolan cements have been made by 
grinding together Portland cement clinker and a pozzolana. The 
quality of the resultant cement was dependent on the nature of the 
clinker, the nature of the pozzolana, and the proportions in which 



I 

: 



- 



they were inter-ground. Assuming that the nature of the materials and 
their proportions are such that a satisfactory pozzolan cement will be 
produced certain beneficial effects may be expected. These are a 
greater resistance to corrosion (sulphate), (Table IV), lower and slower 
heat evolution, and greater workability as far as cohesiveness or fatti- 
ness is concerned (Table V). The disadvantages are slower setting and 
slower rate of development of strength. They may also require some- 
what higher water content for a given consistency than would a normal 
Portland cement. 

TABLE No. IV 

Resistance to 10% sodium sulphate of 1:5:6 concrete made with 
fly ash 20% cements.* 



Compressive Strength at 6 mo, 
Exposed 
to Sodium 

Fly Ash Sulphate Unexposed 

None 6310 5560 

No. 1 6950 7120 

No. 2 6800 6580 

No. 3 6650 6400 

No. 4 6420 5830 

No. 5 5480 5060 



lbs./sq. in. 

Ratio-Exposed 

to 

Unexposed 

0.88 

1.03 

0.97 

0.96 

0.91 

0.93 



TABLE No. V 

Settlement or Bleeding of Concrete before Hardening 









Depth in 


Inches below 


Cement 




Condition 


Original level at 24 hours 


Normal Portland 




Undispersed 




.042 


Normal Portland 




Dispersed 




.027 


Pozzolan 




Undispersed 




.027 


Pozzolan 




Dispersed 




.012 


Mix - 


- Cemen 
Sand 


t 400 g. 
450 g. 








Gravel y s ' 450 g. 








Slump (6" cone) 2 in. 








Size of 


specimens 2" x 4" 


cylinders 





In their properties pozzolan cements are very similar to low or 
moderate heat of hardening cements and their applicability would 
presumably be the same. A possible greater "fattiness" of the pozzolan 
cement might constitute some advantage for this type but a choice 
between them and the low heat types would probably be based on 
economic considerations. When suitable pozzolamc matenals are 
plentifully available the pozzolan cements can probably be produced 
at lower cost. 

♦Raymond E. Davis — Properties of Cements and Concretes containing 
Fly Ash, June, 1938. 



[21 






■ 















/ 



jr 















produced from a naturally occurring "cement roc] h has a 

composition similar to that of the Portland cement raw mix. The 
cementitious qualities of the "rock" are developed by burning 
temperatures somewhat lower than those used for pn 
Portland cement clinker. 

In certain respects natural cements are superior to normal Portland 
cement although they vary widely among them one 

natural cement imparts desirable pr<> does not 

necessarily imply thai some other natural cement will do like 
The advantageous proper! ies of rial oral 1 1 ree of 

cohesiveness or "fattiness" which reduces bleeding and 
greater durability, and lower hea ion. The chief disad 

are slower rates of setting and hardening, lower strength, until 

after very long curing, and a I iter req 

consistency. 

There is no agreement on thi i natural 

cements. It may be t hal I hi 

the lower burning temporal are produc< I irface < i lition which fa 
greater water retentivity and hei " the other hand, the 

properties of those cemei en attributed to the menl 

of a higher proportion of air in the mix which ; ribed 

to small amounts of oil or lentally (or purpo luded in 

the cements during their manufacture. es in 

durability might be explains ' hich 

would help to prevent surface >r to inci ntrained 

More probably both influent i 
tion, as also t lie slower set 
caused by slower hydrat ion. 

Natural cements h;r e fail 
to Portland cement. A mix ! >m natural c< ould 

have undesirable pro in that it would be 

and would have insufficienl strength unless cured for a long time, 
of the recent use of natural i i n for highwa 

sumably with the objective of reducing bleeding and and 

thereby preventing scald e road Fig. XI] A and B). Usually 

a 15* o to 20* ! replacement of portland i I 
been used, that is about 1 sa< k il mix. Tl 

reasonable degree of fattiness and air entrainmei 

portion of natural cement produces too mucl fatl 
qualities and entrains too much air SO tl 
concrete is impaired. 

Dispersion Of portland cement will I the 

properties of the concrete similar ired with natura 

replacements. Fattiness or col 
reduced. The greater fattiness mix will 

air entrapment as a factor in durability. This particular prope 
be enhanced by a slight modification of the 
improvements, if secured througl 
instead of by the use of natural 
advantages of the latter. Dispersion pro 
strengths at all ages, does not affect I 



Fig. XII 




Dispersed and undispersed portland cement mixes and a natural 
Portland blend subjected to freezing and thawing cycles using calcium 
chloride for thawing on the top surface. 

Left B. Portland cement concrete- dispersed. 

Center — A. Portland cement concrete undispersed. 

Right — C. Natural portland blend — undispersed. 

Fig. XII] 




itural portland cement blend concrete! 

'i thawing cycles using calcium chloride for 
rtland blend dispensed. 

and blend und 






. 



and permits a lower water-cement ratio instead of a higher one cf. 
Research Paper No. 35). 

It may, therefore, be possible to secure with normal portland cement 
and a dispersing agent those properties which are desirable in the 
portland-natural blend, fattiness and durability, without the lower 
strengths and slower hardening of the blend (Table VI). Whether 
this is the case will depend to some extent on the particular natural 
cement used, as these cements vary quite widely in their properties. 
A recent study showed that of two natural cements one was very effec- 
tive in improving durability whereas the other had no effect in this 
respect. 

An illustration of the production of similar properties to those 
secured with natural cement by dispersion of portland cement is shown 
in Fig. XII (B and C). Here are given photographs of two cement 
blocks made under similar conditions to those encountered in road 
building and finished as would be a road. Their condition after a 
number of cycles of freezing and thawing by the application of calcium 
chloride to the frozen surface shows the reduced bleeding, increased 
durability and resistance to scaling of the dispersed cement mix. 

A cement dispersing agent for portland cement is also a dispersing 
agent for natural cement and will, therefore, produce the same effects 
with a blend as with an all portland cement mix. It is, therefore, 
possible to design a portland-natural blend concrete mix using a cement 
dispersing agent which will show greater improvement in properties 
than will the use of additional cement equal in monetary value to the cost 
of the dispersing agent. This is illustrated by the strength data given 
in Table VI for two concrete mixes, dispersed and undispersed, of 
equal cost. The added resistance to scaling so secured is illustrated in 
Fig. XIII and in Table VII. 



TABLE VI 

Portland and Portland- Natural Cements with Dispersion 



Normal 


Blend-Portland 83 y 2 % 


Portland Cement 


Natural 16'. 


Undispersed 


Dispersed 


Undispersed 


Dispersed 


Cement — lbs. 574 


499 


562 


503 


Sand - lbs. 1134 


1123 


1110 


1132 


Gravel -lbs. 2099 


2070 


2056 


2085 


Water -gals. 31.2 


28.2 


32.9 


29.4 


Slump in. l'x 


VA 


VA 


u, 


Compressive Strength 








Lbs. per sq. in. 








3 days 2630 


2250 


1970 


2075 


7 days 2790 


2910 


2310 


257(i 


28 days 3430 


3750 


2760 


3320 



[25! 



TABLE VII 
Durability — Portland-Natural Cement Blend 

I'ndispersed and Dispersed J 



("ndispersed Dispersed 

443 



24 
1276 



Natural Portland Cement — lbs. 373 

Natural Cement — lbs. 94 

Sand _ Jbs. 1276 

Stone- _ lbs . 1992 1992 

^ ater -gals. 36 29^ 

Slump in. 2 2 

f " c lpss in weight after freezing and thawing 
20 cycles 6.2 14 

50 cycles 40.0 7.4 

r^Ji?^ be pointed °"t that since dispersion and the use of natural 
S b9 i h mcre ^ e *]* fattin , ess of the mix - «'hen a dispersing agent 
desifr! ?th^i a v?. 0rtlan< i l " natUral C ? me . nt blen '' ( ' are shouki be taken to 

moT d ffi,^ ™H aV ° ,d Kf CesSlve fattl ^ SS as this wou,d make finishing 
more difficult and mig ht cause excessive a r entrainment This mav 

be accomplished by avoiding an excessively rich mix and an excessively 
large proportion of natural cement in the blend. ««*s« eij 

The desirability of using portland-natural cement blends is still a 

h^T^Vi ' Mal Subject even w " h «*P«* to highway work it 

has gained little acceptance in other fields. Assuming however that 

are Sesfred'lnd tV 7t Y^ tUra ' C6me , nt blend ' ^nc.l^fattinest 
w?th n- tu rll rllnf i he T^f™" 1 "< P*rt of the portland cement 
with natural cement is contemplated, cement dispersion offers a means 
( " in ;i I^rtlan<l cement mix withouT^he 

J5 - of a portland-natural cement blend ami at 

equa or less cost. If, for some reason, the use of a Dortland-natiir-.l 

Me. then .he mix can be lefl t , ro ^ 
-' economically wit 1, a cement disjersmg agent 

VI. Cements with Grinding Aids 

-rials have been used as grradine aids that is to 

ttdingofcementcUnteto^r&ac^m; 

nK ; ne,s or surface area. Among mSSTAS 

P^e^ytne^SeSffi iKSSRgSES 

(26j 






The Vinsol cement suffers from the same disadvantage as a port- 
land-natural blend in that strengths are lower. This decrease in strength 
appears to be greater for the Vinsol resin cement than for the blend 
and, moreover, it is permanent, that is, with long curing the strength of 
the concrete made with a portland-natural blend will probably equal 
that of a straight portland mix whereas the Vinsol resin cement will 
always show lower than normal strengths. Apparently the loss in 
strength is directly related to the amount of air entrained. Some strength 
data on cements ground with and without Vinsol resin are given in 
Table VIII. It is especially to be noted that, although the water- 
cement ratio is lower for the Vinsol resin cement, due to the replace- 
ment of water by entrained air, the strengths are markedly lower 
instead of higher as would be expected. 



TABLE No. VIII 

Vinsol Resin Ground Cement 





Concrete Mi 


x — Cement 




467 lbs. 










-Sand 




1346 lbs. 










- Stone - 


H" 


1988 lbs. 








Surface 






Compressive Strength 


Unit wt. 


Ce- 


Vinsol 


Area Sq. 


W/c 


Slump 


» Lbs 


. per sq. 


in. 


Lbs./ 


nent 


Resin 


cm. /g. 


gals/sk 


In 


3 days 


7 days 28 days 


cu. ft. 


A 


Xone 


2090 


7.6 


3 


2240 


3220 


4450 


147.5 


A 


03' , 


2125 


7.1 


2 '• , 


2350 


3270 


3410 


It:) >, 


B 


None 


1920 


7.2 


2 ; ( 


3025 


4530 


4775 


148.2 


B 


.03', 


1982 


6.8 


3 


2230 


3150 


3820 


13! i ti 


C 


None 


1665 


7.0 


2H 


2790 


3840 


4950 


151.0 


C 


.03' , 


1650 


6.8 


3 


2085 


:',ltiii 


3770 


145.5 


D 


None 


2100 


7.5 


Wi 


2970 


344<> 


4760 


150.0 


D 


.03'; 


2090 


7 1 


3 


2460 


3250 


3860 


145.5 



It has been observed that the behavior of Vinsol resin cements is 
quite variable. The effect of a given percentage of Vinsol resin, as 
measured for example by the decrease in unit weight of the concrete 
which is an index of the amount of air entrained, seems to vary with 
different cement clinkers; even with clinker from the same mill pro- 
duced at different times. This variation implies that the effectiveness 
of the Vinsol resin with respect to air entrapment, bleeding, segrega- 
tion, fattiness, durability, and strength will vary. In the present state 
of our knowledge these variations are unpredictable. This means that, 
because a certain percentage of Vinsol resin is ground with the cement 
clinker, it does not necessarily follow that the desired properties will 
be secured in the same degree. A better criterion of the effectiveness 
of a Vinsol resin cement than the percentage used would seem to be the 
drop in unit weight of concrete made with the cement in question 
compared with a similar mix from normal portland cement. To find 
this weight loss, however, seems to be a matter of trial and error from 
one lot of cement to another. 

Vinsol resin cements have been offered and to some extent used as a 
substitute for a portland-natural cement blend, to produce similar 

[27 1 



properties in the concrete mix, particularly increased fattiness and less 
tendency towards scaling. They are competitive on a cost basis as 
neither adds substantially to the cost of the concrete. Considering the 
variable performance of the Yinsol resin cement and the losses in 
strength which may result, it would seem that if the quality of work- 
ability which either Yinsol resin cement or the portland-natural blend 
will impart is desired, the choice would be on the latter. 

A cement dispersing agent will disperse a Yinsol resin cement just 
as it will any other type of cement and consequently will have the same 
beneficial effect on the properties of concrete made from this variety of 
cement. The use of a dispersing agent with a Yinsol resin cement, 
however, is not recommended because the variability of these cements 
presents the danger that the dispersing agent with the Yinsol resin may, 
on occasion, produce excessive fattiness and air entrainment. 

Just as in the case of natural cement blends it may be possible to 
produce with normal portland cement and a dispersing agent those 
qualities of fattiness and durability which it is intended to secure with 
a Yinsol resin cement (Fig. XI Y). Likewise these advantages are 
obtained without the lower strengths of the Yinsol resin cements or 
their variability. 












Fig. XIY 




Surface area 1660 sq. cm. g. 
A No. 108 — Compressive strength at 28 days - - 3210 
B Xo. 115- 
C No. 112 

Concrete Mix 
Cement 
Sand 
Stone - 
Water - A - Plain 

B - Yinsol resin 
C - Dispersed 



28] 



28 " 


2260 


28 " 


4630 


467 lbs. 




1346 lbs. 




1988 lbs. 




38 


gals. 


35 y 2 gals. 


35K2 


gals. 






A comparison of a Vinsol resin cement with normal portland cement 
and a dispersing agent from an economic point of view is even more 
favorable for the latter than it would be if compared to undispersed 
Portland cement or to portland-natural blends. If it is assumed that a 
Vinsol resin cement will cost approximately the same as a similar 
normal portland cement a rough comparison may be made. A loss in 
strength, if the Vinsol resin is effective, of about 20 r 7 may be expected. 
This is roughly equivalent to the strength imparted by one sack of 
cement. Assume now that a mix of 4000 lbs. sq. in. is desired and that 
a mix containing 5 sacks of normal portland cement will produce a 
strength of 3000 lbs./sq. in. Now, by the addition of a dispersing agent 
at a cost of approximately $0.30 per cu. yd. a strength of 4100 lbs. will 
be secured. By the addition of one extra sack of portland cement at 
a cost of $0.50 per cu. yd., a strength of 3900 lbs./sq. in. will be secured 
(cf. Fig. VII Research Paper No. 36 for these strength data). With the 
Vinsol resin cement which has lost 20% of the strength of the original 
mix, that is, has reduced the strength of the 5 sack mix to 2400 lbs./sq. 
in., in order to realize 4000 lbs./sq. in. it will be necessary to add 
approximately 2 sacks of extra cement at a cost of $1.00 per cu. yd. 
In other words, for a given strength, it will cost 20c more per cubic 
yard with an undispersed normal portland cement compared with the 
cement with a dispersing agent, and 70c more per cu. yd. with the 
Vinsol resin cement (Table IX). There does not appear to be any 
economic justification for the use of Vinsol resin cement. 

TABLE IX 

Sacks Compressive Cost — Dollars Additional 

Cement Strength (Cement plus Cost per 

Type of Cement per Lbs. per Dispersing Cu. Yd. 

Cu. Yd. Sq. In. Agent) Dollars 

Normal portland cement 5 . 3000 2 . 50 

Vinsol resin cement 5 . 2400 2 . 50 

Normal cement dispersed 5.0 4100 2.80 

To produce 4000 lb. concrete. 
Normal portland cement 6.0 3900 3.00 0.20 

Vinsol resin cement 7.0 4000 3.50 0.70 

Normal cement dispersed 5 . 4100 2 . 80 

Rosin, beef tallow, oil, and similar materials are very similar to 
Vinsol resin. Like this last they also impair strength. On the whole 
such information as is available would indicate that they are less 
satisfactory than Vinsol resin and there is no evidence that they have 
received any general acceptance although some experimental highway 
installations have been made. 

As far as the relation of these grinding aids to cement dispersion 
is concerned it is the same as the relation between \ insol resin 
ground cements and dispersion but, if anything, less favorable to 
the grinding aids. 

These cements can be dismissed with the statement that the same 
properties, if desired, can be secured with Vinsol resin or a portland- 
natural cement blend to better advantage. It follows that these prop- 

[29] 



produced more economically and without the 
- loss in strength by use of a cemeni 

ground with grinding aids ii 

menl dispersing agent may bTgWnd 

widely used grinding aid contamVaTa 

Such cemente are in an entirely 

ound with Vinsol resin beef tallow 

produced and large quantities of 

■-..•n.> in ih..,im|K-r ties f'.l 

pear thai there are also^X* other 

dingl I ,,,,1,,,^ 

• 



\ ill. \\ sterproof < emeata 



ebeen manufactured 

a smaT amount of some 
probably ahTfanctta! to 
is to Sake "the 
epellanl that" 
oidsintheconcn 
......pliS 

capillary attraction 

HI,.,,., 
parati 

itic pn-s 

■ 

me of cxceaa 





















" "■' ''••;-'.ii,i lo ii>rr<n- 



, 



'< 



^ 



r>rou#'i 









# / 

i ' 

/ ' / 
/ ' / 
| t / 

f '/ 
/ j 

i i f 
II 















SUMMARY 

• • en thai there an- available a number of special cements 
velop some particular property of the cement 

I e Mian would be the rase in a normal Portland cement. 

either without substantial change in the other 

■ expense of one or more of these other 

erties winch it has been Bought to improve in this 

ons, are early strength, corrosion (sul- 

dration, capillarity, and workability in the 

3S. This last property has also hem 

ir and increased durability. 

■ lalh applicable to the special cements as it 

• i ' I i ame effect on them in reducing 

consistency and making available a 
1 < k>nsequently n has similar eff< 

volume chai gth and 

>mical means of producing a con- 
to Lilar t\ pe of cement. Often n | 

rt) without I lie attendant di 
he relation i | dispcr 

i 'i on in three w.-r 

• re rum be 
emei and a disp< 

■ the 
produced bj high < 
i i Lent with respect 

inability a- found in po/.xolan 

• i round w nh grinding 

.Hon alio holdj 

Lant '1 \ pe \ 
dified low (, 

' ■ • n : ■ 
al cement and a normal 

i rid on t i i /) ;i r 

antial \. 

•■■ " /- '" 'hi ituation foi the low heat cements 'J ype IVj 















■n^M r<i? .• ;,/«' ' ;,-.,: i .,,. S |„. ( i;i , . 4 . f r if Jfi , , 



There is no conflict betwe 

•ersing agent beai 
economically and wi\ \\ re 

to normal port land cement I 
can be iecured al 
dispersing agent ; in ot hei 
and t he dispersii 
appear de arable to u e i 
car be realized ai minim i 
of cement di pei ion 

\i.i>ti r Builden Research Lab 
c L \ i land, i ^ln» - 






MASTER BUILDERS 

PRODUCTS EMPLOYING 

THE 

CEMENT DISPERSION PRINCIPLE 

The principle of dispersion of cement is applicable to any type of 
work involving cement in mortar or concrete. This work is of a very 
varied nature and for different applications somewhat different proper- 
ties are required. To accomplish these purposes most economical I \ 
the cement dispersing agent may be combined with other basic principles 
for the improvement of specific properties of concrete and mortar, as 
illustrated by the diagram below. These include pozzolanic activity, 
stearate waterproofing, chemical hardening, and metallic aggregates. 

The Master Builders Company has developed a group of products 
adapted to various specific concrete and mortar applications. The 
exclusive dispersing agent is incorporated in each of these products 
in a manner to impart the maximum effect on the resultant structure 
at minimum cost. These products are as follows: 

Application Product 

Concrete (General) Pozzolith 

High Early Strength Concrete High Early Pozzolith 
Concrete (Exposed to Capillary 

Moisture) Omicron Waterproofing 

Floors — Heavy Duty ..Masterplate 

Floors — Light Duty Mastermix 

Colored Floors Colored Metalicron and Colormix 

Brick Mortar Omicron Mortarproofing ("0. M.") 

Colored Brick Mortar Colored Omicron Mortarproofing 

Grouting and Maintenance Embeco 

PRODUCT COMPOSITION DIAGRAM 



C£MfNT 

Piast/ozIng 

Water Reovcrton 





THE MASTER BUILDERS COMPANY 



Factories in Cleveland 
and Buffalo 



CLEVELAND, OHIO 



Sales Offices in 
All Principal Cities